Changes

==Fault detection methods==

==Fault detection methods==

Dipmeter or borehole image data can be used to establish if and where any faults cut a well.<ref name=Bengtson_1981>Bengtson, C. A., 1981, [http://archives.datapages.com/data/bulletns/1980-81/data/pg/0065/0002/0300/0312.htm Statistical curvature analysis techniques for structural interpretation of dipmeter data]: AAPG Bulletin, v. 65, no. 2, p. 312–332.</ref> <ref name=Bengtson_1982>Bengtson, C. A., 1982, [http://archives.datapages.com/data/specpubs/basinar2/data/a130/a130/0001/0000/0031.htm Structural and stratigraphic uses of dip profiles in petroleum exploration], in M. T. Halbouty, ed., The deliberate search for the subtle trap: AAPG Memoir 32, 351 p.</ref> <ref name=Goetz_1992>Goetz, J. F., 1992, [[Dipmeters]], ''in'' D. Morton-Thompson and A. M. Woods, eds., Development geology reference manual: [http://store.aapg.org/detail.aspx?id=612 AAPG Methods in Exploration Series 10], p. 158–162.</ref> <ref name=Adamsanddart_1998>Adams, J. T., and C. Dart, 1998, The appearance of potential sealing faults on borehole images, in G. Jones, Q. J. Fisher, and R. J. Knipe, eds., Faulting, fault sealing and fluid flow in hydrocarbon reservoirs: Geological Society (London) Special Publication 147, p. 71–86.</ref> A sharp change in dip amplitude or azimuth on a dipmeter log can indicate that a fault is present. Drag patterns may also be seen on the dip data above and below the fault intersection in the well ([[:file:M91Ch13FG80.JPG|Figure 2]]).

Dipmeter or borehole image data can be used to establish if and where any faults cut a well.<ref name=Bengtson_1981>Bengtson, C. A., 1981, [http://archives.datapages.com/data/bulletns/1980-81/data/pg/0065/0002/0300/0312.htm Statistical curvature analysis techniques for structural interpretation of dipmeter data]: AAPG Bulletin, v. 65, no. 2, p. 312–332.</ref> <ref name=Bengtson_1982>Bengtson, C. A., 1982, [http://archives.datapages.com/data/specpubs/basinar2/data/a130/a130/0001/0000/0031.htm Structural and stratigraphic uses of dip profiles in petroleum exploration], in M. T. Halbouty, ed., The deliberate search for the subtle trap: [http://store.aapg.org/detail.aspx?id=375 AAPG Memoir 32], 351 p.</ref> <ref name=Goetz_1992>Goetz, J. F., 1992, [[Dipmeters]], ''in'' D. Morton-Thompson and A. M. Woods, eds., Development geology reference manual: [http://store.aapg.org/detail.aspx?id=612 AAPG Methods in Exploration Series 10], p. 158–162.</ref> <ref name=Adamsanddart_1998>Adams, J. T., and C. Dart, 1998, The appearance of potential sealing faults on borehole images, in G. Jones, Q. J. Fisher, and R. J. Knipe, eds., Faulting, fault sealing and fluid flow in hydrocarbon reservoirs: Geological Society (London) Special Publication 147, p. 71–86.</ref> A sharp change in dip amplitude or azimuth on a dipmeter log can indicate that a fault is present. Drag patterns may also be seen on the dip data above and below the fault intersection in the well ([[:file:M91Ch13FG80.JPG|Figure 2]]).

An anomalously thin reservoir section, perhaps in conjunction with the absence of a reasonably persistent marker horizon, may be caused by a normal fault cutting out part of the stratigraphic section in a well ([[:file:M91Ch13FG81.JPG|Figure 3]]). The thickness of missing section can be estimated by comparison to nearby wells with unfaulted sections.

An anomalously thin reservoir section, perhaps in conjunction with the absence of a reasonably persistent marker horizon, may be caused by a normal fault cutting out part of the stratigraphic section in a well ([[:file:M91Ch13FG81.JPG|Figure 3]]). The thickness of missing section can be estimated by comparison to nearby wells with unfaulted sections.